A new study out of Yale University offers evidence that coal mining isn’t directly to blame for Appalachia’s health problems—but it could play a part.

For years, researchers have tried to figure out why people in Appalachia contract diabetes, heart disease and various cancers at higher rates than most of the country. Several studies out of West Virginia University found links between some of those maladies and coal mining. The new study, from researchers at Yale’s School of Public Health, suggests the causes are more complicated.

“In fact they did not see the report, receive a copy of the report until it had actually been published,” he said.

The NMA was looking for research to counter several studies done by Michael Hendryx at WVU, who has found links between coal mining pollution and human health, including higher cancer rates and birth defects.

Borak included all the counties defined by the federal government as “Appalachia” in his study, a swatch which stretches from Mississippi to New York. He concluded that a variety of factors contribute to pockets of poor health and high mortality in the region, including geography, lack of access to health care and culture.

“I don’t think this gets anybody off the hook,” he said. “I just don’t think that the issue here has to do directly with pollution. I think it has to do with a very complicated set of socioeconomic, cultural, behavioral kinds of factors which have really disadvantaged some of these people.”

Borak says mining companies have a responsibility to help improve conditions in their workforce and communities.

“Bad health in those communities isn’t good for them,” he said. “It isn’t good for their productivity, it isn’t good for their money and it isn’t good for their reputations. And it shouldn’t be good for their souls, either, I guess.”